Player-piano action



G. BEDFORD.

PLAYER PIANO ACTION.

APPLICATION FILI-Ip sEPT.24. |920.

1,419,849. PalteufeaJune 13, 1922.

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WWA A Y lllmluil) uqihmuml'll" .-'EYLWVTQA A UNITED STATES y GEORGEBEDFORD, 0F TORONTO, ONTARIO, CANADA.

PLAYEEPIANO ACTION.

Specification of Letters Patent. Patented June 13, 1922 Applicationfiled September 24, 1920. Serial No. 412,479.

\ T 0 all w kom t may con/cern:

lie it known that I, GEORGE BEDFORD, of the city of Toronto, yin thecounty of York, Province of Ontario, Canada, a subject of the King ofGreat Britain, have invented certain .new and useful Improvements inPlayer-Piano Actions, of which the following is a specification.

This invention relates particuhtrly to the striking` pneumatics oi aplayer-piano and the valve mechanism through the medium of which thepneumatics are controlled by the passage of the music roll over thetracker bar, and my object is to devise a construction which will enableany individual valve mechanism tobe quickly removed without disturbingother parts, and which permits of ready access to the under sides of thediahraoms ofthe valve mechanisms. Another object is to make the valveactionas silent as possible.

I attain my objects by means of the constructions hereinafter describedand illustrated in the accompanying drawings in which- Fig. 1 is avertical section of part of a player-piano mechanism illustrating myinvention; v

lig. 2 a plan view of part of the air trunk, an

Fig. 3 a side elevation of a valve casing with the connecting diaphragmchamber.

In the drawings like numerals ot reference indicate corresponding partsin the different figures.

1 is part of the frame oi the action supporting the horizontal air trunk2. This air trunk has a series of recesses 3 formed therein, one Yforeach valve mechanism. Secured to the air trunk below each recess 3 is apneumatic 4t, which actuates one of the hammers of the piano action (notshown). I show the pneumatic as connected with a striker wire 5connected with the lever 6 suitably fulcrumed on the -trame. 7 is thevalve casing, which is provided with the usual valve chamber 8 providedwith the alined valve seats 9 and 10, the valve seat 9 communicatingwith the atmosphere and the valve seat 10 with the air trunk 2. A valve12 of ordinary construction controls the passages through these valveseats. The upper part of the valve stem passes loosely through a hole ina felt washer 13. This felt washer therefore acts as a guide to thevalve stem, while permitting the free pas- `the under side ot' the valvecasing, thus serving to strengthen the connection between the valvecasing and the diaphragm chamber.

The diaphragm 17 is of ordinary construction and is engageable'with thelower end of the valve stem in the usual manner. A bleed 18 is formedbetween the diaphragm chamber and the interior of the air trunk.

An opening is formed in the under side of l the valve casingcommunicating with the valve chamber `8, which opening, when the valvecasing is in position, is in alinement with the air duct 19 in the solidmaterial. of the air trunk, which air duct communicates with theinterior of the pneumatic. The valve casing is detachably secured inposition, the preferred construction for that purpose beingsubstantially as follows. A block or rib 20 is formed on or secured tothe upper side of the air trunk, which block has a series of recesses 21formed therein one Vfor each valve casing. Each valve casing has a pin22 inserted in its end, which pin is adapted to engage in the recess 21.The reverse arrangement is, of course an alternative.

The opposite end of each valve casing is releasably held. `down by meansof a latch 23 pivoted either on the valve casing or the air trunk andengaging a pin 24. Preferably an alining pin 25 is inserted in the airtrunk adapted to enter a hole formed in the under side of the valvecasing.

As the mode of operation of a valve of the type shown is well known inthe art, a detailed description is not necessary. It will be noted,however, from the description and from the drawings that each individualvalve casing with its attached diaphragm chamber is easily and quicklyremoved without disturbin any part of the mechanism other than t ecommunication with the tracker bar. Repairs and renewals are thus madeWith a minimum oit trouble.

llihat l claim as my invention is 1. In a player-'piano action, thecombination of an air trunk having a recess in one side; a. pneumaticconnected to the aii' trunk; a valve casing` having a diaphragm chamberconnected therewith and detz'lehabl;7 se cured to the air trunk With thediaiphragm chamber received Within the recess, said YValve casing anddiaphragm chamber being` removable as a. unit; and an air duct leading`:trom the pneumatic, the valve casing having a passage leading itrom thevalve chamber adapted to register with said air duct when the valvecasinggis in place.

2. A.. playerpiano action constructed as set 'forth in `claim l providedwith a'bleed in the Wall of the diaphragm chamber leading into the airtrunk.

In avplayer-piano action, the combinaoit an air trunk having a recess inone and an air duct leading :from the said through to the opposite side;a pneumatic connected to the air trank and communicating with the airduct at the least .mentioned sidevo't the air trunk; a valve cas ing`haring a diaphragm chamber connected therewithand detachably secured tothe air trunk with the diaphragm chamber received Within theireccss andthe Valve chamber of the casinf` in communication with the air ductaforesaid.

Ai, A player-piano action constructed as set-'forth in claim l in whichthe means for detachably connecting the valve casing to the air trunkcomprises a block on the air trunk having a recess in its side vfacingthe valve casing; a pin on the Valve casing` adapted to enter said hole;and a latch detachably holding' the opposite end ot the valve casing tothe air trunk.

5. A player-piano action constructed as setiorth in claim 1 in which thediaphragm chamber is ot L-shape, the leg; o' the L foiiming;` thetracker bar communication.

6. In a player-piano action, a valve casing' trai/ing;` a valve chambertherein provvided with alined yValve seats facing one another; a valveadapted to engage either seat and provided with a tixed stem; and av:telt Washer secured to the casing having' an aperture therein throughwhich the. `valve stom passes su'iiiciently small to guide the valrestem and maintain the valve in alinement with the seats While permittinga sufficiently free passage of air.

Signed at Toronto, Canada, this 11th day ot September, 1920,

GEORGE BEDFORD.

